摘要
为了缩短硫氧镁水泥(MOSC)的凝结时间,提高其早期力学性能,以蔗糖为分散剂,用不同水化活性的氧化镁(MgO)粉制备了MOSC,分析了蔗糖对MOSC凝结时间、水化性能、抗压强度、物相组成、微观形貌和孔结构的影响.结果表明:活性为75.0%的MgO粉较活性为65.5%的MgO粉制备的MOSC凝结时间更短,早期抗压强度更高;蔗糖作为分散剂更适用于活性为75.0%的MgO粉制备的MOSC体系,通过其空间位阻效应的发挥,改善新拌浆体的流动度,延长新拌浆体的初凝时间和终凝时间,还能抑制Mg(OH)_(2)的生长,降低硬化浆体的孔隙率,提高其28 d的抗压强度;蔗糖可促进MOSC吸收大气中的CO_(2)形成MgCO_(3)晶体.
To shorten the setting time and improve the early mechanical property of magnesium oxysulfate cement(MOSC),MOSC was prepared using magnesia(MgO) powder with different activities,and sucrose was used as a dispersing agent.The effect of sucrose on the setting time,hydration performance,compressive strength,phase composition,microstructure and pore structure of MOSC was investigated.The results show that,compared with samples prepared using MgO powder with 65.5% hydration activity,the setting time of MOSC prepared using MgO powder with 75.0% hydration activity is shorter and its early compressive strength is higher.Sucrose is preferable to MOSC prepared using MgO powder with 75.0% hydration activity.The sterically hindered effect of sucrose improves the fluidity of fresh MOSC paste,prolongs the initial and final setting time,inhibits the formation of Mg(OH)_(2),reduces the total porosity and enhances the 28 d compressive strength of hardened MOSC paste.The addition of sucrose is beneficial for MOSC to absorb CO_(2)in the atmosphere to form MgCO_(3).
作者
许星星
李晶
陈啸洋
余红发
关岩
XU Xingxing;LI Jing;CHEN Xiaoyang;YU Hongfa;GUAN Yan(School of Materials and Metallurgy,University of Science and Technology Liaoning,Anshan 114051,China;School of Chemical Engineering,University of Science and Technology Liaoning,Anshan 114051,China;Department of Civil Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China;Reseach Institution of Keda Fengchi Magnesium Building Materials,Anshan 114051,China)
出处
《建筑材料学报》
EI
CAS
CSCD
北大核心
2023年第2期193-199,共7页
Journal of Building Materials
基金
国家重点研发计划资助项目(2020YFC1909304)
国家自然科学基金资助项目(51778101)。
关键词
硫氧镁水泥
活性氧化镁粉
蔗糖
水化进程
抗压强度
水化产物
孔结构
magnesium oxysulfate cement(MOSC)
active magnesia powder
sucrose
hydration process
compressive strength
hydration product
pore structure
